After an 18 year career at Apple, Peter Oppenheimer is calling it quits.

Apple said Tuesday that Oppenheimer, its longtime chief financial officer, will retire in September. Luca Maestri, the company’s corporate controller and vice president of finance, will succeed him, beginning his transition into the role in June.

Maestri, who joined Apple in March of 2013 after serving as CFO for both Nokia Siemens Networks and Xerox, has been widely viewed as the company’s CFO-in-waiting.

“When we were recruiting for a corporate controller, we met Luca and knew he would become Peter’s successor,” Apple CEO Tim Cook said in a statement. “Luca has over 25 years of global experience in senior financial management, including roles as a public company CFO, and I am confident he will be a great CFO at Apple.”

During Oppenheimer’s tenure as CFO, Apple’s annual revenue increased to $171 billion from $8 billion — a more than 2000 percent increase. The company also implemented a major share repurchase program and cash dividend.

Oppenheimer said in a statement that after nearly two decades at Apple, he wants to spend more time with his family, become more involved at California Polytechnic State University and finish his pilot’s license. On Monday, he was named to the board of Goldman Sachs as an independent director.